# Heat and Piston Cylinder Device

Topics: Heat, Thermodynamics, Heat transfer Pages: 3 (1061 words) Published: December 14, 2011
Individual Assignment. Each student is required to complete the task in a full handwriting on an A4 paper. Due Date of Submission on 30th November 2011, before 2.00 PM. Late submissions will not be entertained.

1. A 1.8-m rigid tank contains steam at 220°C. One third of the volume is in the liquid phase and the rest is in the vapor form. Determine (a) the pressure of the steam, (b) the quality of the saturated mixture, and (c) the density of the mixture.

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2. A piston–cylinder device contains 0.85 kg of refrigerant-134a at 10°C. The piston that is free to move has a mass of 12 kg and a diameter of 25 cm. The local atmospheric pressure is 88 kPa. Now, heat is transferred to refrigerant-134a until the temperature is 15°C. Determine (a) the final pressure, (b) the change in the volume of the cylinder, and (c) the change in the enthalpy of the refrigerant-134a.

3. Determine the specific volume of superheated water vapor at 10 MPa and 400°C, using (a) the ideal-gas equation, (b) the steam tables. 4. Determine the specific volume of superheated water vapor at 3.5 MPa and 450°C based on (a) the ideal-gas equation, (b) the steam tables. 5. A 3.27-m3 tank contains 100 kg of nitrogen at 175 K. Determine the pressure in the tank, using (a) the ideal-gas equation. Compare your results with the actual value of 1505 kPa. 6. A 1-m3 tank contains 2.841 kg of steam at 0.6 MPa. Determine the temperature of the steam, using (a) the idealgas equation 7. A piston–cylinder device initially contains 0.07 m3 of nitrogen gas at 130 kPa and 120°C. The nitrogen is now expanded to a pressure of 100 kPa polytropically with a polytropic exponent whose value is equal to the specific heat ratio (called isentropic expansion). Determine the final temperature and the boundary work done during this process. 8. A mass of 5 kg of saturated water vapor at 300 kPa is heated at constant pressure until the temperature reaches 200°C. Calculate the work done by the steam during this process....